FeedRite Feeding Tube. Alex Heilman Graham Husband Katherine Jones Ying Lin

Size: px

Start display at page:

Download "FeedRite Feeding Tube. Alex Heilman Graham Husband Katherine Jones Ying Lin"

Dulcie Turner
5 years ago
Views:

1 FeedRite Feeding Tube Alex Heilman Graham Husband Katherine Jones Ying Lin

2 Problem Statement Gastric bypass is an invasive procedure that requires up to 5 days of hospitalization and has a narrow patient population (those with a BMI greater than 40 or greater than 35 with obesity-related conditions; roughly 18 million Americans) in comparison with the rate of obesity in America (78.6 million Americans; defined as BMI > 30). In addition, gastric bypass can cost ~$25,000 (depending on state of residence), reducing the number of patients who receive the procedure to 1% of those who qualify. Current analogs to gastric bypass use naso-duodenal feeding tubes that rely on repeated fluoroscopic procedures and several hours for proper tube placement.

3 Needs Assessment Wider Availability a. Feeding tube must require 1 outpatient appointment for placement b. Must be portable such that it can be used throughout a hospital c. Primary placement tool must be detachable from tube after placement Confident Placement a. Device must integrate a second method that ensures proper tube positioning b. Device must verify differences between stomach and duodenum c. Device must provide real-time updates of tube position Safer a. Device must be radiation-free b. Tubing must be biocompatible

4 Background Problems: Obesity, Type II Diabetes Solution: Gastric Bypass Surgery The stomach is divided into upper, smaller portion and lower, larger portion. The smaller portion is reconnected to the jejunum while bypassing the duodenum. May reverse diabetes, lose weight Invasive, risky and expensive For patients with BMI > 40, or BMI > 35 with obesity-related conditions

Background Alternative Solution: Naso-duodenal Feeding Tube For patients with BMI > 30, or unqualified for gastric bypass surgery because of age or

5 Background Alternative Solution: Naso-duodenal Feeding Tube For patients with BMI > 30, or unqualified for gastric bypass surgery because of age or physical conditions Existing device - Cortrak EAS Our design - less expensive, confident placement, placement detection will not interfere with feeding

6 Potential Market Obesity and Type II Diabetes - 9 % of American adults Gastric Bypass Procedures - 180,000 per year Marketing: Medical professionals at hospitals Individual patients at home

7 Evidence Tran K, Brun R, Kuo B. Evaluation of regional and whole gut motility using the wireless motility capsule: Relevance in clinical practice. Therap Adv Gastroenterol. 2012; 5:

8 Design Computer Display Sensors Arduino Standard NG Tube

9 Design Micro Pressure Sensor Standard NG Tube Micro ph Sensor

10 ph Probe Setup

11 ph Calibration Used Atlas Scientific s prescribed sensor calibration method Compared sensor reading to three known ph values at 4, 7, 10 Expected ph Value Average % difference per data point % % %

12 ph Probe Calibration

MS5803-14BA Pressure Sensor Gel coated sensor May or may not need to waterproof board I2C connection Possibility to use SPI as well

13 MS BA Pressure Sensor Gel coated sensor May or may not need to waterproof board I2C connection Possibility to use SPI as well Appropriate range, resolution, operating temperature zone, and response time Initial calibration Measured mmhg Actual mmhg % Error 1.96%

14 Tubing Provided by: VitalityMedical Polyurethane Important dimensions: Diameter and Length 1cm markings Feeding port Clog-free tip

Physiology of Gastrointestinal System--pH Saliva (ph range 6.5-7.5) Stomach (ph range 1.5-2.

15 Physiology of Gastrointestinal System--pH Saliva (ph range ) Stomach (ph range ) Parietal cells secrete HCl G cells secrete gastrin Chief cells secrete pepsinogen Purpose of low ph: immune barrier to microorganisms, activate digestive enzymes

16 Physiology of Gastrointestinal System--pH Duodenum (ph brought to 7) Cholecystokinin (CCK) stimulates release of bile from gallbladder Secretin stimulates the release of sodium bicarbonate from pancreas Brunner s glands produce alkaline secretion Purpose of ph: Activate intestinal enzymes for absorption, deactivate digestive enzymes for breakdown, protect intestinal lining Jejunum (ph up to 8) Colon (ph stable about 7-7.5)

18 Physiology of Gastrointestinal System-- Pressure as a Secondary Indicator Pressure profile (Kuo et al. [2010]): Stomach: 4790 {3091, 6933} mmhg/s Small intestine: 5182 {2791, 7538} mmhg/s Wide range of pressure in both stomach and small intestine - difficult to differentiate based merely on pressure Solution: examine the frequency and magnitude of pressure spikes instead of actual pressure measurements (lower average level and more constant in stomach, higher average level and more pulsatile in small intestine)

Testing Chamber As the tube goes down the cylinder, sensors will detect the changes of pressure and ph at the same time - simulation of feeding tube s passage along digestive system Advantages

19 Testing Chamber As the tube goes down the cylinder, sensors will detect the changes of pressure and ph at the same time - simulation of feeding tube s passage along digestive system Advantages Pressure change: height of cylinder P = Pa + pgd ph change: three layers of solution with different ph Layers formed by solutions with different densities Much safer Less hazardous materials Easier to build and modify Easier to understand for audiences

20 Testing Chamber Increasing depth and increasing density contribute to increasing pressure readings P = ρgd Estimating 1.00 g/ml, we should have a change of 73.5 mmhg in one meter Swan Isopropyl Alcohol, 99% ph 7 density: 0.785g/mL Heinz Distilled White Vinegar ph 2.4 density: 1.01 g/ml Dawn Ultra Concentrated Dishwashing Liquid ph 9 density: 1.06 g/ml

21 Expected Pressure Changes P = ρgd Depth (feet) Expected Pressure (mmhg)

22 Testing at CELA Upper GI SimMan! Advantages: Includes major landmarks in GI tract Test size and shape of tubing Camera and lighting to confirm length of tube necessary and proper placement Disadvantages Sensors will not detect changes in ph Cannot insert through nasal cavity Material interaction will not be same as with body Cannot test biocompatibility and friction

23 CELA Testing tubing in upper GI model Place camera (CELA) within tube as we guide tube down GI tract Identify position of landmarks to mark expected changes in ph and pressure Optimize length of tubing to minimize extra materials Additional indication of estimated placement of feeding tube in average patient

24 Additional Design Components Casing to improve portability User Interface LED screen to display simple output Bluetooth communication for wireless device Eliminate breadboard

25 Parts Necessary Additional Design Components LED Screen 3D Printed Casing Bluetooth communication PVC pipe has not been delivered

26 Future Directions CELA Test and optimize size of tubing Mark points of interest along GI tract to indicate estimated location Calibrate pressure sensor once PVC Piping arrives Meeting with Dr. Abumrad Begin outlining future designs using microsensors Create easy-to-use UI Portable housing

27 Grant Proposal Modifications Additional design components Calibration of ph and pressure sensors

Chapter 20 The Digestive System Exam Study Questions

Chapter 20 The Digestive System Exam Study Questions 20.1 Overview of GI Processes 1. Describe the functions of digestive system. 2. List and define the four GI Processes: 20.2 Functional Anatomy of the